#define _CRT_SECURE_NO_WARNINGS
#pragma warning(disable:6031)
#include"Date.h"
using namespace std;

int Date::GetMonthDay(int year, int month)
{
	assert(month > 0 && month < 13);
	int monthday[13] = { 0,31,29,31,30,31,30,31,31,30,31,30,31 };
	if (year == 2 && ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)))
	{
		return 29;
	}
	return monthday[month];
}

Date::Date(int year, int month, int day)
{
	_year = year;
	_month = month;
	_day = day;
}

Date::Date(const Date& d)
{
	_year = d._year;
	_month = d._month;
	_day = d._day;
}

Date& Date:: operator=(const Date & d)
{
	_year = d._year;
	_month = d._month;
	_day = d._day;
	return *this;
}

Date::~Date()
{
	_year = 0;
	_month = 0;
	_day = 0;
	cout << "~Date()" << endl;
}

bool Date:: operator==(const Date& d)
{
	return _year == d._year &&
		_month == d._month &&
		_day == d._day;
}

bool Date:: operator != (const Date& d)
{
	return !(*this == d);
}

bool Date:: operator>(const Date& d)
{
	if (_year > d._year)
	{
		return true;
	}
	else if (_year == d._year)
	{
		if (_month > d._month)
		{
			return true;
		}
		else if (_month == d._month)
		{
			if (_day > d._day)
				return true;
		}
	}
	return false;
}

bool Date:: operator < (const Date& d)
{
	if (_year < d._year)
	{
		return true;
	}
	else if (_year == d._year)
	{
		if (_month < d._month)
		{
			return true;
		}
		else if (_month == d._month)
		{
			if (_day < d._day)
				return true;
		}
	}
	return false;
}
bool Date:: operator >= (const Date& d)
{
	return !(*this < d);
}

bool Date:: operator <= (const Date& d)
{
	return !(*this > d);
}

Date& Date:: operator+=(int day)
{
	_day += day;
	while (_day > GetMonthDay(_year, _month))
	{
		_day -= GetMonthDay(_year, _month);
		_month ++ ;
		if (_month == 13)
		{
			_year++;
			_month = 1;
		}
	}
	return *this;
}

Date Date:: operator+(int day)
{
	Date tmp = *this;
	tmp._day += day;
	while (tmp._day > GetMonthDay(tmp._year, tmp._month))
	{
		tmp._day -= GetMonthDay(tmp._year, tmp._month);
		tmp._month++;
		if (tmp._month == 13)
		{
			tmp._year++;
			tmp._month = 1;
		}
	}
	return tmp;
}

Date& Date:: operator-=(int day)
{
	_day -= day;
	while (_day <=0)
	{
		_day += GetMonthDay(_year, _month);
		_month--;
		if (_month == 0)
		{
			_year--;
			_month = 12;
		}
	}
	return *this;
}

Date Date:: operator-(int day)
{
	Date tmp = *this;
	tmp._day -= day;
	while (tmp._day <= 0)
	{
		tmp._day += GetMonthDay(tmp._year, tmp._month);
		tmp._month--;
		if (tmp._month == 0)
		{
			tmp._year--;
			tmp._month = 12;
		}
	}
	return tmp;
}

Date& Date::operator++()
{
	return *this += 1;
}

Date Date:: operator++(int)
{
	*this + 1;
	Date tmp = *this;
	return tmp;
}

Date& Date::operator--()
{
	return *this -= 1;
}

Date Date:: operator--(int)
{
	*this - 1;
	Date tmp = *this;
	return tmp;
}
int Date:: operator-(const Date& d)
{
	Date max = *this;
	Date min = d;
	int flag = 1;
	int n = 0;
	if (*this < d)
	{
		max = d;
		min = *this;
		int flag = -1;
	}
	while (min != max)
	{
		++min;
		++n;
	}
	return n * flag;
}











